Discovered a new resource today (and just in time to help with car selection): the ACEEE Greener Cars report. They charge for the full report (under $10) but offer free “green driving tips” where I finally learned what those black, accordion-looking plastic devices on gas pumps are: vapor-recovery nozzles. A good thing. Since you have to buy gas, try to use the right pump.
Must also give a nod to the Low Impact Living newsletter, where I found the link.